For some years now, due to the incorrect use that some companies or people made of emails, Google has put in place a whole series of restrictions to prevent the phenomenon of spam and to protect the security of users from continuous phishing attempts. For this purpose it has imposed a threshold of maximum emails that can be sent or received in a day and has introduced a limit number of recipients allowed to the message. It is not a novelty in fact to run into warnings or error messages that prevent the correct functioning of the mailbox such as:
- “You have reached a limit for sending mail” that appears if you try to send a single email to more than 500 recipients or if you exceed the limit of 500 daily mails sent. It will take 1 to 24 hours before you can send new mail with the advice to do so the next time you create a Google group with all recipients so you don’t get blocked.
- “Messages you sent couldn’t be delivered” is displayed instead if the recipient’s address is invalid or has a number of incoming messages that is too high. Also in this case the advice is to wait a few hours to be able to send the message, useful time also to verify the validity of the recipient’s address.
- “The user you are trying to contact is receiving mail at a rate that prevents additional messages from being delivered.” means instead that the contact you want to reach has too much incoming mail and that therefore you will have to find another way to contact him more quickly.
Prevent the emails’ blocking
Google itself provides a whole series of useful tips to prevent mail messages from being blocked, marked as spam or even worse that Gmail limits the frequency of sending for a period of time. A series of best practices that are useful both for those who use a simple Gmail account and for those who use a Workspace work account for advertising or information purposes. In order for emails from your domain not to be blocked or end up in the Spam folder, which means that they will never appear, you will have to:
- Configure reverse DNS records that are valid for each IP address that is linked to your domain.
- Send all messages from the same IP address unless the purpose of the message is different. A different IP is recommended for each purpose.
- Do not mix different content types in the same email alert. For example, do not include content on promotions when the purpose is to send the receipt.
- Messages in the same category must have the same email address in the header From: (From:) that describes the purpose (received)
- Use URLs on the Status page of Safe Browsing sites to verify that the domain you are using is not listed among the unsafe ones or is linked to one of the same type.
- Do not send sample phishing messages or test campaigns from your domain since they affect the reputation of the domain and lead to blocking.
7.Do not use other domains or senders without permission, a practice known as spoofing, which can cause Gmail to classify messages as spam.